How can create icon animated for dock?
which software do you used to make png files?
I downloaded ani files but are a series of images like a animation, I can't produce this tipe of png.
Sorry for my English

Actually, that's a very good question.
The kind of "animated" PNGs we use here, aren't exactly animated, in the strict sense. It's just a single PNG image, with all the frames one next to the other. For instance, if we had an animation which is 100x100 pixels, and 25 frames, our image would be: 2500x100 pixels (25 x 100) x 100, since the 25 frames would be arranged horizontally.
As far as I know, only one piece of software exists for that job, and it's included in CursorFX from Stardock. You'll have to install their free version, and then look in the installation directory (ex. C:\Program Files\Stardick\CursorFX\) for an .exe called "AniUtil.exe". Also, when creating the animation, your animation sequence will have to be numbered with leading zeros too, or else, the animation will be out of sequence. Like, if your animation has 30 frames, the first frame will have to be 01. If your animation has 130 frames, the first one will have to be 001, etc. All frame numbers will have to have the same digits as the biggest one.
Now, that's a point. I could make a little proggie to do that better. Hmm...
In order to create such an animation from an ANI file, you will have to find some programme to extract the frames as independent files, and then convert them to PNG (from whatever).

thanks
I used "AniUtil.exe" but the resulting file is not recognized as an animation.
There are a minimum or maximum number of frames?
Particular size etc. ..

There's something wrong with your animation, mate. Firstly, I see 31 "frames" and the image resolution is 5475x180. You will notice that 5475 / 180 = 30.4166... also, 5475 / 31 = 176.6129... which means, it cannot be divided by either its height OR the number of frames. Which means, you've done something wrong. OK, Winstep has no idea about how many frames you have there, it will only divide width by height and compute frames. But the fact that even the frame number is non-divisible (I mean, it doesn't produce an integer) shows that you've done something wrong. Finally, the PNG is interlaced-encoded. I wouldn't do that. Always store frames in progressive mode.
Now, there are a few simple rules, which I thought were obvious. All your frames must be the same size. Exactly the same size. Also, all your frames must be of the same colour depth and of the same encoding, i.e. progressive.
Try again...

Thank you,
resolved, is very important that height and width of the frames have same size and that the png file is not interlaced

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